This invention relates to composite trusses used for supporting floors, roofs and other structural components, and particularly relates to a key clip support member which is used to connect the chords and webs of the truss.
Prior art trusses have been assembled by forming a web, generally of metal composition, in a zig-zag pattern and securing the webs to elongate chords, usually by means of forming a notch or recess in the chord and securing the web to the chords by means of a pin which extends laterally through the chord and web. This configuration produces a truss which is of diminished structural integrity due to the holes which are drilled to receive the pins.
Another form of connecting a web to a chord is disclosed in U.S. Pat. No. 3,537,224 to Troutner, wherein the webs are attached to a case which is received in a substantially rectangular recess formed in the chord. The case includes flanges which contact two sides of the chord, securing the web to the chord without the necessity of drilling a hole through the chord.
Although the case-enclosed web is suitable for its intended purpose, the cases formed on the web require strengthening to prevent buckling during loading. Although the cases are not structurally complex, their manufacturing process involves more distinct steps than desired. Additionally, the flanges which secure the web to the exterior side of the chords are restricted in size due to the assembly procedures which required the flange to pass through the recess formed in the chord.
It is therefore an object of the present invention to overcome the drawbacks and limitations with the prior art proposals. More specifically the invention has the following objects:
(1) to provide a key clip truss wherein a case-retaining clip is provided to secure a case to a chord;
(2) to develop a case-retaining clip which includes a flange of relatively large surface area on the exterior side of a chord;
(3) the provision of a web case which is easily and inexpensively constructed and which has a high decree of structural integrity; and
(4) to provide a composite truss which has increased load bearing capability without requiring an increase in the thickness of the chords or the webs.